Suspension device for the bowl of a scraper

ABSTRACT

Suspension device for the bowl of a scraper having draft arms vertically swingably supported by a draft tube attached to a goose neck horizontally swingably mounted on the scraper, the bowl being swingably supported at the free ends of the draft arms. One end of each of a pair of lift cylinder assemblies is arranged at the left and the right side with respect to the center of the scraper body and connected through spherical bushes to the upper rear portion of the goose neck at positions relatively close to each other while the other ends of the lift cylinder assemblies are connected through spherical bushes to a cross member laterally spanning the bowl at positions adjacent to opposite ends of the cross member so that the lift cylinder assemblies extend obliquely permitting the length thereof to be increased so as to improve the stability in the operation of the bowl while the strength of the suspension device is improved.

United States Patent Umeda et al. 1 Dec. 2, 1975 [54] SUSPENSION DEVICEFOR THE BOWL OF 3,100,945 8/1963 Bernotas 37/129 UX A SCRAPER 3,115,71612/1963 Hein et al. 37/129 [75] Inventors: Haruhiko Umeda, Yokohama;Primar y ExammerLeo Friagha a :P Akm both of Attorney, Agent, orFirm-Armstrong, Nikaido &

awasa 1, a of Japan wegner [73] Assignee: Kabushiki Kaisha KomatsuSeisakusho, Tokyo, Japan [57] ABSTRACT 22] Filed; Jam 30 1975 Suspensiondevice for the bowl of a scraper having draft arms vertically swingablysupported by a draft [21] Appl' N05 545,497 tube attached to a gooseneck horizontally swingably mounted on the scraper, the bowl beingswingably 30] Foreign Application priority Data stt pported at the freeendls o; the drafLlarm s. One end A 8, 1974 n 0 each of a pair of liftcy 1n er assem ies 15 arranged pr Japan 49 39063 at the left and theright side with respect to the center 52 us. C1 37/126 R; 37/010. 9;280/492' the scraper body and Connected thmugh Spherical 37/l29 bushesto the upper rear portion of the goose neck at v 2 positions relativelyclose to each other while the other [51] Int. Cl. E02F 3/86 [58] Fieldof Search 28O/492 37/126 R 129 ends of the lift cylinder assemblies areconnected u 37/616 through spherical bushes to a cross member laterallyspanning the bowl at positions adjacent to opposite [56] ReferencesCited ends of the cross member so that the lift cylinder assembliesextend obliquely permitting the length UNITED STATES PATENTS thereof tobe increased so as to improve the stability 2 13 Aulstm 37/129 UX in theoperation of the bowl while the strength of the 2 931 451 4i19 0 ISuspension device is improved 3,028,694 4/1962 Creighton 37/129 3Claims, 9 Drawing Figures US. Patent Dec. 2, 1975 Sheet 1 of2 3,922,803

F I 6 IA PRIOR ART i P b i FIG. /B

j PRIOR ART t. l t 6/ /d c l FIG. 2A PRIOR ART A d FIG. 2B

i PRIOR ART i l a y U.S. Patent Dec. 2, 1975 Sheet 2 of2 3,922,803

FIG. 3/1

PRIOR ART ff ART SUSPENSION DEVICE FOR THE BOWL OF A SCRAPER BACKGROUNDOF THE INVENTION The present invention relates to a suspension devicefor the bowl of a scraper. In general, the prior art teaches variousways in which the bowl of a scraper is connected to a goose neck of thetractor so that it can be lifted and lowered.

One of the prior art connecting means comprises gimbals mounted on theopposite ends of the draft tube of the bowl supported by the goose neckand lift cylinder assemblies which are freely supported by gimbals. Thebowl is connected to the scraper body through the lift cylinderassemblies so that the bowl is controlled by the operation of the liftcylinder assemblies. However, such connecting means requires specialparts for the gimbals which are heavy and bulky thereby raising the costwhile a large space is required for the gimbals. Further since thegimbals are mounted on the draft tube which is subjected to a hightwisting stress it is the portions of the draft tube at which thegimbals are secured must therefore be reinforced so as to prevent stressconcentration therein. Further, the visibility in the rearwarddirection'is infaired.

Another prior art connecting means comprises trunnions supported by thegoose neck which trunnions laterally support the lift cylinderassemblies swingably. However, such connecting means lacks reliabilityin operation and strength, because no traverse freedom is given to thetrunnions in case the bowl moves transversely or is twisted therebyresulting in excess force at the point where the trunnions are mountedon the goose neck. Further, since the lift cylinder assemblies areconnected to a cross member spanning transversely the bowl at positionsrelatively close to the center thereof, the cross member is subjected toa high bending movement thereby impairing its strength.

A further prior art connecting means comprises upstanding supportbrackets secured to the upper surface of the goose neck. The liftcylinder assemblies are connected to the brackets through sphericalbushes, however, such connecting means have the disadvantage that theheight of the brackets supporting the lift cylin der assemblies is quitehigh thereby impairing the strength therefore and detracting from theappearance of the scraper. Further, the greater height of the scrapergives rise to difficult problems in the use of the scraper.

The present invention aims at avoiding the above described disadvantagesof the prior art connecting means for the bowl in a scraper.

SUMMARY OF THE INVENTION The object of the present invention is toprovide a novel and useful suspension device for the bowl of a scraperwhich eliminates the disadvantages of the prior art scraper suspensiondevice.

The above object is achieved in accordance with the present invention byproviding a suspension device for the bowl of a scraper having a gooseneck horizontally swingably mounted on the scraper, draft armsvertically swingably supported by the goose neck at their proximal ends,whereby the draft arms are swingably supporting the bowl at their distalends and a pair of lift cylinder assemblies are arranged at the left andthe right side with respect to the center of the scraper body 2 andconnected to brackets on the goose neck and the bowl for controlling themovement of the bowl. The suspension device is chracterized in that oneend of each of the pair of lift cylinder assemblies are connectedthrough spherical bushes to the brackets positioned at the upper rearportion of the goose neck relatively close to each other and the otherends of the lift cylinder assemblies are connected through sphericalbushes to a cross member spanning laterally the bowl at positionsadjacent to the opposite ends of the cross member whereby the lifecylinder assemblies extend obliquely.

With the arrangement described above, the stability and strength of thesuspension device are insured even where the bowl moves laterally,because the length of i the lift cylinder assemblies is increased andthe spherical bushes are incorporated in the means connecting the liftcylinder assemblies to the goose neck and the bowl, respectively.

Further, the spherical bushes are easily available in the market therebymaking it possible to construct and maintain the suspension device at alower cost in comparison with the prior art in which gimbals are used.

Further, since the lift cylinder assemblies are connected to the upperrear portion of the goose neck, sufficient strength is given to thesuspension device with the minimum number of parts and simpleconstruction.

Still further, the bending movement generated in the cross member isreduced to a minimum by virtue of the supporting points of the liftcylinder assemblies being located on the cross member of the bowladjacent to the opposite ends thereof so as to dispose the lift cylinderassemblies in obliquely extending state, while the stability of thescraper is improved even when the bowl moves laterally.

Further, the visibility in the rearward direction is improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. IA is a plan view showing anexample of the prior art suspension device for the bowl of a scraper;FIG. 1B is a vertical elevational view of FIG. 1A;

FIG. 2A is a plan view showing another example of the prior artsuspension device;

FIG. 2B is a vertical elevational view of FIG. 2A;

FIG. 3A is a side view showing a still further example of the prior artsuspension device;

FIG. 3B is a vertical elevational view of FIG. 3A;

FIG. 4 is a general side view showing an emobidment of the scraperincorporating the suspension device constructed in accordance with thepresent invention;

FIG. 5 is a vertical elevational view of FIG. 4; and

FIG. 6 is a fragmentary view in enlarged scale showing a portion of thelift cylinder assembly shown in FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Prior to thedescription of the present invention, some of the prior art suspensiondevices will be described for better understanding of the presentinvention.

Referring to FIGS. 1A and 1B which show an example of the prior artsuspension device the gimbals b are mounted on the opposite ends of thedraft tube a swingably supported by the goose neck d which is swingablymounted on the scraper (not shown). The draft arms i secured to thedraft tube a at the opposite ends thereof 3 swingably support the bowl Aas shown. The gimbals b freely support the lift cylinder assemblies asshown, and the lift cylinder assemblies c are connected to the crossmember h of the bowl A so that the movement of the bowl A is controlledby the actuation of the lift cylinder c. However, as describedpreviously, such a construction has the disadvantage that special partsare necessary to construct the gimbals b thereby raising the .rearwarddirection is impaired.

' Another example of the prior art suspension device is shown in FIGS.2A and 2B which comprises trunnions 'e secured to the goose neck d. Thetrunnions e support lift cylinder assemblies 0 laterally swingably, andthe lift cylinder 'assemblies c are connected to the cross member h ofthe bowl A so as to control the movement of the bowl A by'the actuationof the lift cylinder assemblies 0. However, as previously described,this construction has the disadvantage that excess force is generated inthe lift cylinder assemblies 0 in case the bowl is moved laterally,because no lateral freedom is given to the lift cylinder assemblies 0,while very high bending movement is given to the cross member h.

A further example of the prior art suspension device is shown inv FIGS.3A and 3B which comprises upstanding support bracketsfsecured to theupper surface of the goose neck a, and lift cylinder assemblies 0 areconnected between the bracketsfand the cross member 11 of the bowl A asshown so that the movement of the bowl A is controlled by the actuationof the lift cylinder assemblies c. As described previously, thisconstruction has the disadvantage that the supporting points of thebrackets fis made elevated so that the strength as well as theappearance is impaired, and the height of the scraper is unreasonablyhigh.

Now, a preferred embodiment of the present invention eliminating theabove described disadvantages will be described below with reference toFIGS. 4 to 6.

As shown in the drawings, the goose neck 2 is hori- 'zontally swingablymounted on the tractor 1 and the draft arms 3 are vertically swingablymounted on the goose neck 2 by the draft tube 4 as shown. The bowl 5 isswingably mounted on the free ends of the draft arms 3.

In accordance with the characteristic feature of the present invention,brackets 6a, 6b are secured to the upper rear end of the goose neck 2 inpositions relatively close to each other at the left and right sidesrespectively with respect to the center of the goose neck 2. One end ofeach of the lift cylinder assemblies 9a, 9b are connected respectivelyto the brackets 6a, 6b

through spherical bushes 10, respectively, as best shown in FIGS. 5 and6, while the other ends of the lift cylinder assemblies 90, 9b areconnected through spherical bushes 10 to brackets 8a, 81) secured to thecross member 7 of the bowl 5 adjacent to the opposite ends thereof,respectively, as shown in FIG. 5. Thus, the lift cylinder assemblies 9a,9b extend obliquely thereby permitting the length thereof to beincreased so that the supporting action of the bowl 5 is improved.

The brackets 6a, 6b and the cross member 7 are shown as being verticallyaligned. However, the cross member 7 may be located forwardly 0rrearwardly of the brackets 6a, 6b in the longitudinal direction of thetractor 1 beneath the brackets 6a, 6b so that the lift cylinderassemblies 9a, 9b extend obliquely forward or rearward, or obliquelyforwardly and laterally or rearwardly and laterally, thereby permittingthe length of the lift cylinder assemblies 9a, 9b, to be furtherincreased facilitating the provision of the spherical bushes l0 andincreasing .the stability of the operation of the bowl.

As described previously, the above construction also makes it possibleto lower the production and maintenance cost with the minimum number ofparts easily available and to improve the visibility in the rearwarddirection while sufficient strength is given without additionalreinforcement heretofore required in the prior art suspension device.

We claim:

1. In a suspension device for the bowl of a scraper having a goose neckhorizontally swingably mounted on the scraper, draft arms verticallyswingably supported by said goose neck at their proximal ends, saiddraft arms swingably supporting said bowl at their distal ends, and apair of lift cylinder assemblies arranged at the left and the right sidewith respect to the center of the scraper body and connected to saidgoose neck and said bowl, respectively, for controlling the operation ofsaid bowl, the improvement wherein one ends of said pair of liftcylinder assemblies are connected through spherical bushes to the upperrear portion of said goose neck at positions relatively close each otherand the other ends of said lift cylinder assemblies are connectedthrough spherical bushes to a cross member spanning laterally said bowlat positions adjacent to the opposite ends of said cross member wherebysaid lift cylinder assemblies extend obliquely.

2. The suspension device of claim ll, wherein said cross member isdisposed at a position forward of said upper rear portion of the gooseneck where the lift cylinders are connected.

3. The suspension device of claim ll wherein said cross member isdisposed at a position rearward of said upper rear portion of the gooseneck where the lift cyl-

1. In a suspension device for the bowl of a scraper having a goose neck horizontally swingably mounted on the scraper, draft arms vertically swingably supported by said goose neck at their proximal ends, said draft arms swingably supporting said bowl at their distal ends, and a pair of lift cylinder assemblies arranged at the left and the right side with respect to the center of the scraper body and connected to said goose neck and said bowl, respectively, for controlling the operation of said bowl, the improvement wherein one ends of said pair of lift cylinder assemblies are connected through spherical bushes to the upper rear portion of said goose neck at positions relatively close each other and the other ends of said lift cylinder assemblies are connected through spherical bushes to a cross member spanning laterally said bowl at positions adjacent to the opposite ends of said cross member whereby said lift cylinder assemblies extend obliquely.
 2. The suspension device of claim 1, wherein said cross member is disposed at a position forward of said upper rear portion of the goose neck where the lift cylinders are connected.
 3. The suspension device of claim 1 wherein said cross member is disposed at a position rearward of said upper rear portion of the goose neck where the lift cylinders are connected. 